When I turn on my printer, the menu screen flashes on and off. You  see small black flashing  "blocks" on the screen where words should appear. If I press the "X" button on the printer, sometimes the wording "USER MODE" appears. Thereafter if I press any button the flashing resumes.

I have tried deleting the printer on my PC and then reinstalling it, but the printer can not be found. This is  with the USB plugged in, or when I try to  install as a wireless  printer. 

I assume that the problem is probably in the printer ( am not technical minded)?  Also, I have failed to ascertain what "user mode" means! I would mention that the printer was working OK up to a couple of days ago.

Any help will be appreciated.